Liquid and vacuum cleaning machine



Oct. 27, 1959 GRINDLE ETAL 2,909,800

' LIQUID AND VACUUM CLEANING MACHINE Filed June 22, 1953 5 Sheets-Sheet 1 F'lEi 'l INVENTORS 7 Eugene L. Grin /6 [award 6. P/c/(e/S HTTORNE Y5 Oct. 27, 1959 n GRlNDLE ETAL 2,909,800

LIQUID AND VACUUM CLEANING MACHINE Filed June 22, 1953 5 Sheets-Sheet 2 INVENTORS 5/96/76 A, Grmd/e 7 By fawara 6. p/cke/s g vid 37 A 7'TORNE Y5 Oct. 27, 1959 GRINDLE ETAL 2,909,800

LIQUID AND VACUUM CLEANING MACHINE Filed June 22, 1953 5 Sheets-Sheet 3 waw ATTORNEYS Oct. 27, 1959 GRINDLE ET AL 2,909,800

LIQUID AND VACUUM CLEANING MACHINE Filed June 22, 1953 5 Sheets-Sheet 4 L. INVENTORS Eugene L. 6/ //7d/ fdwara 6. /cA e/s ATTORNE Y5 San Mateo, and Edward G. Pickels, Atherton, Calif Application June 22, 1953, Serial No. 363,312

24 Claims. c1. 15-321 I Eugene Grindle,

The invention relates generally to apparatus for the separation and removal of dust and other foreign mater'ial from air. One embodiment of the invention described herein pertains more particularly to apparatus for cleaning'floors, rugs or carpets, draperies and other smooth or textured surfaces. In addition, the invention pertains to centrifugal separating devices and to the construction of liquid pumps.

In copending application, Serial No. 217,536, filed March 26, 1951 for a liquid vacuum cleaner now abandoned, there is disclosed an apparatus including an applicator head adapted to be traversed over a surface to be cleaned, and provided with an inlet opening. The head is connected to the suction side of a blower through a flow path which includes separating means of the filter type. The applicatorheadis provided with means for discharging liquid uponf'the surface being cleaned, and which is connected to a liquid pump through a manually operated valve. Liquid thus delivered on the surface being cleaned is immediately removed by the stream of air, whereby the liquid together with dirt or the foreign material removed from the surface being cleaned, is'delive red by the air stream to the separating means. Apparatus of this type is highly effective for cleaning various materials and surfaces, including carpets, rugs, draperies, floor surfaces and the like. Theliquid medium may be water, with or without additives such as dissolved soaps or detergents. The ease and effectiveness with which such apparatus can be used is dependent upon a number of structural and operating features including particularly the means employed for separating and collecting foreign material. While it is possible to use filtering devices such as disclosed in said copending application, the flow resistance involved considerably reduces the suction upon the applicator head; also the removal of dirt from such filtering means is troublesome and dilficult. The construction of the applicator head is important to obtain effective cleaning action, and to insure removal of the liquid to prevent uncontrolled wetting or running of the liquid. In general when cleaning surfaces such as carpets it is desirable to remove as much liquid as pos sible, while at the same time applying the liquid in such a manner as to insure adequate cleaning. Also we have found that" many textured surfaces require a scrubbing action to dislodge dirt and other foreign material. After a cleaning operation it is desirable that the surface retain as little as possible of the liquid, thus facilitating subsequent drying without mildewing.

In general it is an object of the present invention to provide a new and improved machine of the above character having novel means for separting out dirt and like foreign material.

Another object of the invention is to provide a new and improved machine of the above character having a novel assembly of the working parts which facilitates manufacture and its use by relatively unskilled operators.

.Another object of the invention is to provide a new and improved applicator head for machines of the above United States Patent ice 2 character," which is more effective and ,flexible in its cleansing action and in its removal of liquid from the surfaces being cleaned or treated. p v

Another object of the invention is to provide anovel centrifugal separator for the removal of dirt and like foreign material, and which is useful in machines of the above character, or in other machines or equipment where analogous problems are involved. I I

Another object of the invention is to provide'a new and improved type of liquid pump which is particularly suitable for use in machines of the above character.

Another object of the invention is to provide a novel apparatus for the cleaning of air and for the removal of dust and like foreign material. v I) Further objects and features of the invention will appear from the following description in which the preferred embodiment of the invention has been set forth in detail in conjunction with the accompanying drawing.

Referring to the drawing:

Figure 1 is a side elevational view in section illustrating a part of the complete machine incorporating the present invention. v I p Figure 2 is a cross-sectional view taken along the line 22 of Figure 1.

Figure 3 is a cross-sectional detail taken along the line 33 of Figure 1. V

Figure 4 is a cross-sectional detail taken along the line 44 of Figure 1.. v V

Figure 5 is a cross-sectional detail taken along the line 55 of Figure 4.

Figure 6 is a cross-sectional detail taken alonggthe line 66 of Figure 4. I v v Figure 7 is a side-elevational view illustrating the applicator head and associated parts. I

Figure 8 is a cross-sectional view taken along the line 88 of Figure 7. I

Figure 9 is a cross-sectional view taken along the line 9-9 of Figure 7. I

Figure 10 is a cross-sectional view on an enlarged scale taken along the line 10-10 of Figure 7.

Figure 11 is a cross-sectional view on an enlarged scale taken along the line 11-,11 of Figure 10. V

Figure 12 is a cross-sectional view on an enlarged scale taken along the line 1212 of Figure 7.

Figure 13 is a cross-sectional view taken along the line 1313 of Figure l2.

Figure 14 is a cross-sectional view taken along the line 14 14 of Figure 13. v

Figure 15 is a cross-sectional detail illustrating the means fordischarging liquid in conjunction with the applicator head.

The embodiment of the apparatus illustrated in the drawing consists of a housing 10 (Figure l) which is formed to provide a lower part 10a, and a removable top part 10b. The principal parts of this housing can be made of suitable sheet metal. The lower part 1011 provides a liquid reservoir 11, and a bottom sump 12 which connects with the liquid removal pipe 13. The sump is covered by the screen 14. The housingcan be supported by the casters 15 foreasy movement over a floor.

The top housing part 10b is shown provided with a flangededge 16, to facilitate seating upon the upper edge 17 of the lower housing part. The two parts can be releasably clamped together by suitable meanssuch as. clamping devices 18 of the toggle type. 3

The top housing part serves to mount the electric driving motor 21, which is provided with a conventional starting switch 22, and is adapted to be connected toa suitable source of current supply by means of the extension cord 23. The vertical shaft 24 of the motoris directly connected to the blower 26. While various types of blowers can be used, it is desirable to use one of the multi-stage type, having two centrifugal runners 27 and 28, disposed within the blower housing 29. The blower has an inlet or suction opening 31, which draws air from the interior of the housing and discharges it through the ports 32. A dished annular shield 33 is shown extending over the ports 32, and serves to retain a simple dust filter medium 34, which can be made of a loose fibrous material. The arrOWs in Figure 1 indicate the direction of movement of air into the opening 31, through the stages of the blower, and then through the ports 32 and through the filter medium 34 to the atmosphere.

Within the housing we provide centrifugal separating means designated generally at 36. It consists of a shallow pan-like bowl 37, having a flat bottom wall 38, and a raised and slightly conical rim 39. It is convenient to form this bowl of pressed or spun sheet metal. The upper edge 41 can be reinforced and functions as a discharge or overflow lip. Seated upon the bowl 37 there is an entrainment device 42 consisting of a top annular wall 43 and a downwardly depending rim 44 which is cylindrical. Suitable means, such as the spring retaining fingers 46, facilitate removable retention of the entrainment device 42 upon the bowl, with the fingers 46 engaging the lip 41. Entrainment device 42 serves as means for supporting mat 48, which can be of coarse felted or matted fiber, and which serves to retain and separate out foreign particles, such as dirt and the like. The mat 48 is normally held in place by suitable means such as the studs 49.

It is desirable to provide a strainer 51 extending inwardly from the lip 41 of the bowl and through which liquid must pass before being received by the entrainment device 42. This screen or strainer can be made of suitable material such as fine metal gauze, or a nonmetallic material such as coarse nylon cloth or netting. Its one edge 52 can contain an elastic cord whereby the outer margin can be engaged over the lip 41. The inner edge can be reinforced by a light metal ring 53. The inner edge of the wall 43 of device 42 can be provided with a downwardly turned flange 54, which extends through the ring 53.

As will be presently explained the screen or strainer 51 serves to separate out stringy material such as hair, bits of thread, wool or cotton lint, or fiber and the like. Such material forms a filter medium through which the liquid passes, and which serves to remove some of the dirt particles. The mat 48 serves to separate out the remainder of the foreign material in the liquid.

The mounting means for the centrifugal separator includes the plate 56, which is carried by the legs 57. The legs are inclined outwardly, and their lower portions 59 are formed of resilient material, such as suitable rubber. It will be noted that the lower ends of these legs are seated in the corners of the housing 10, thus minimizing lateral displacement, and generally centering the plate 56.

The plate 56 serves to mount the vertical stud shaft 61 and this shaft forms a part of a journal assembly. The remaining parts of the assembly include the sleeve 62, the balls 63, and the bushing 64. The balls engage the upper conical end face of the shaft 61, while the bushing 64 generally centers the sleeve 62 with respect to the shaft. This assembly is retained together by suitable means, such as a flange 66 on the lower end of sleeve 62 which is engaged by the lug 67. The sleeve 62 is proportioned to fit within a socket recess 68 formed in the hub 69, the latter being fixed to the bottom wall 38 of the separator bowl.

With the arrangement described above the bowl 36 is carried for free rotation by a vertical axis, and the supporting means is cushioned by virtue of the resilient rubber leg portions 59. The bowl can be readily lifted from the journal assembly and returned to normal operating position after a cleanout operation.

The bowl 37 is rotated by impingement of air discharging from the nozzle 71. This nozzle is located to one side of the hub 69, and it has a lower open end 72 which is inclined at a small angle to the horizontal (Figure 1) to discharge air downwardly and with a direction component tangential to the separator bowl. As viewed in plan (Figures 2 and 3) the opening 72a in the lower face 72 of the nozzle is substantially elliptical. The air passage 73 of the nozzle is in communication with the pipe 74 which extends upwardly and is carried by a fitting 76 where it communicates through the housing top portion 10b. Fitting 76 also forms a swivel attachment for the exterior L pipe section 77, and this connects with an exterior extension hose or conduit as will be presently described. A tube 78 communicates with the interior of pipe 74 as shown in Figure l, and serves to introduce liquid into the air stream as will be presently described.

The blower housing 29 preferably carries a shell 79 which has its lower open end terminating within the separator bowl 37. The inlet opening 31 of the blower is in free communication with the interior of the shell. The lower end of the shell 79 is shown provided with leg extensions 81 which can be used to support the entire top assembly of the machine when it is removed from the lower part. The nozzle 71 and pipe 74 can be in part secured to and supported by the shell 79, as illustrated.

The top assembly also serves to mount the liquid pump 82. This pump has a suction fitting 83 connected to a suction tube or hose 84 which connects with a fitting 86 on one side of the housing top 10b. Fitting 86 is detachably coupled to the suction tube or hose 13. The pump also has a discharge fitting 87 which is connected by the tube or hose 88 with the tube 78 (Figure 1). A second discharge fitting 89 is connected by the tube or hose 91 to a fitting 92 which is mounted in the top housing part 10b. A flexible tube or hose is detachably coupled to the fitting and extends to the applicator head as will be presently described. The pump 82 is driven by suitable means, such as the belt 94 (Figure 2) which engages the sheaves 95 and 96, mounted upon the motor and pump shafts respectively.

While various types of liquid pumps can be used it is preferable to employ one of the gear types such as illustrated in Figure 4. Thus the interior of the pump body 101 is bored to receive the gears of 102, 103, and 104. Assuming rotation of driving gear 102 in a clockwise direction as viewed in Figure 4, a liquid is drawn from fitting 83 and the pump inlet space 106 and discharged by impeller gears 103 and 104 through the space 107 and fitting 89. Fluid pressure operated valve means is provided whereby when the pump is operating and the discharge through fitting 89 is shut off, the pressure developed is sufficient to open the valve means and discharge liquid through the fitting 87. Also this valve means forms a part of an automatic priming arrangement. The valve means which we have shown for this purpose consists of a valve member 108 which is carried by the valve rod or stem 109. A bushing 111 is slidably fitted within the bore 112, and is yieldably held in place by the compression spring 113 and the threaded plug 114. The space 112 behind the bushing 111 is vented to the outlet side of the valve 108 by duct 115. Valve rod 109 is slidably retained by bushing 111, and is urged toward closed position by the loading spring 116. Under static conditions the valve 108 is held in slightly open position with respect to seat 117, by engagement of collar 118 with bushing 111 as shown in Figs. 4 and 5. When the pump and blower are placed in operation the flow of air through pipe 74 produces a partial vacuum in pipes 78 and 88 and in space 107 because pipe 91 is closed by valve 151. This partial vacuum sucks liquid from the reservoir into the pump through the suction pipe or hose 84 to effectively prime the pump. Assuming that liquid is being discharged through the fitting 89 (Figure'4), fluid pressure moves bushing 111 against spring113 a distance suflicient to fully close valve 108. When discharge through fitting 89 is shut off the resulting increased outlet pressure overcomes the force exerted by spring 116 and opens valve 108 to deliver liquid through hose 88 and pipe 7 even though bushing 111 is still depressed.

In Figures 7 to 13 inclusive we have shown a suitable form of applicator head 121 and associated parts, which can 'be used with the machine described above. As shown particularly in Figure 7 the applicator head is adapted to be coupled to the rigid tube sections 122 and 123 which are connected to the flexible hose '124. The hose is coupled to the swivel pipe section 77.

i The head 121 includes a portion 121a which is of increased width, and which provides a surface 126 adapted to be placed in contact with a surface to be treated, such as a carpet, etc. This surface 126 is in part formed by the flanges 127 and 128, and is interrupted by the spaced slots 129 and 131. Ribs 132 and 133 preferably extend across these slots 129'and 131 for a purpose to be presently described. An elongated inlet opening 134 ex-- tends upwardly from the surface 126, and merges with the air flow passage 136 in the head. In transverse section, surface 126 can be slightly convex as illustrated.

A liquid pipe 137 is provided on the head for discharge of liquid. This pipe extends substantiallythe entire width of the head. (Figure 14) and is accommodated within the recess 138. It is provided with a plurality of discharge orifices 139, which discharge downwardly through the slot 141 in the head and toward the area of the inlet opening 134. To provide simple means for retaining the pipe 137 in a desired operating position, we provide removable fittings 142 (Figure 14), which are threaded into the adjacent portions of the applicator head, and which provide closure plugs 143 extending into the open ends of the pipe 137. The plugs are sealed with respect to the pipe by suitable means such as resilient sealing rings 144 of the O-ring type. By loosening one of the fittings 142 the angular position of the pipe 137 can be adjusted as desired. When the fittings 142 are tightened the pipe 137 is held in a desired position. It may be explained that in various types of cleaning and treating operations it is desirable to adjust the pipe 137 to obtain a desired action of the jetting liquid upon the surface being cleaned or treated. As a part of the head assembly we provide a swivel connection 146 to the L pipe section 147. This pipe section is adapted to be secured by a conventional quickly detachable coupling 148, to the adjacent end of the tube section 122. The other end of tube section 122 has a similar quick-detachable coupling 149 to the tube section 123.

Liquid is supplied to the applicator head through valve means and a series of pipe sections as follows: A suitable small liquid valve 151 (Figures 7 and 11) is mounted upon the tube section 123. It is provided with a manual operating member 152, and can'include a valve member 153 which is normally urged toward closed position by the spring 153a. A flexible hose section 154, which can be made of transparent plastic material, connects from the valve 151 to a quick-detachable coupler 155 (Figure 1) which makes connection with the fitting 92. The hose section 154 can be conveniently retained by clamping bands or like means to the flexible air hose 124. Another flexible hose section 156, which likewise can be made of transparent material, connects with the other side of the control valve 151, and is provided with a quick-detachable coupling 157 adapted for attachment with the liquid nozzle pipe 137. The inlet part 154a for the valve is preferably located adjacent the valve seat (Figure 11) whereby the force of flowing liquid tends to make the member 152 stick in open position, thus requiring manual closing. I I I "6 Operation of the machine described above is as follows: With the parts assembled as in Figure 1, a quantity of liquid is placed in thelower housing part 1 0a, up to a level which may be near that (i.e. slightly below) of the plate 56. Assuming that a floor carpet or like surface is to be cleaned, a suitable non foaming soap or detergent is addedto the liquid. The parts are now assembled in the manner illustrated in Figure 1, by applying the separator bowl, and then seating and clamping the top housing part 10b with the parts carried by the same, in the manner illustrated. Now the machine is put into operation by energizing the motor 21. The blower draws air through the applicator head and into the housing, where it is discharged with downward, and tangential velocity components in the manner previously described. The resulting impingement upon the bottom wall 38 of the separator bowl causes this bowl to turn'at a speedsuflicient for the desired separating action, as for example speeds of the order of from 500 to. 800 r.p.m. :Assuming that the pump has been primed and that the liquid valve 151 has remained closed, the pump continuously Withdraws water from the space 11. at the lower end of the housing, and delivers such water pastthe valve 108, through the pipes 88 and 78 andinto the airstream flowing to the pipe 74 and being delivered from the nozzle 71. Thus the air being withdrawn from the applicator head is continuously intermixed with a sprayof Water and such droplets of water are continuously collected within the separator bowl 37, and caused to flow over the lip 41, into theentrainment device 42. y In the entrainment device the liquid flows through the mat 48, to be .finally delivered back into the lower part of the housing.

While the valve 151 remains closed the operator may use the applicator head in a manner comparable to an ordinary vacuum cleaner, by drawingit over surfaces from which dirt and dust are to be removed. Any such dirt or dust particles which are picked up by the flowing air stream are washed out of the air by the water spray within the housing, and are ultimately removed.

The hair, fragments of thread, or like fibers are removed from the surface being cleaned, and delivered into the separator bowl, they are held by the screen 51, thereby forming a mat within the separator bowl which serves in part as a filter medium. Removal-ofhair and like fibers in this manner is desirable not only to form a filter medium, but in addition to prevent suchmaterial from clogging and interfering with the desired operation of the matting 48. The liquid flows through the matting before its discharge and here remaining particles of dust or dirt are enmeshed or entrapped, whereby clarified liquid is finally discharged. i a

. Assuming now that it is desired to obtain the added cleansing action of liquid upon the surface being cleaned, the operator opens valve 151 by pulling the operating member 152, whereby valve member 108. automatically closes, and liquid is discharged from the orifices of the pipe 137 (Figure 13). The resulting fine water jets discharge contra to the flow of air through the orifice 134, to'impinge upon the surface in which the applicator head is operating. However, immediately after such impingement the liquid is picked up from the surface being cleaned, and is entrained with the air stream for return to the housing. Ribs 132 and 133 serve to deflect the inrushing air downwardly into the carpet or rug being cleaned, thus enhancing the pickupof dirt or dust when operated without liquid, and also improving the pickup of liquid when water is being applied.

The pipe 137 can be adjusted in accordance with the character of the surface being cleaned. For example, if the surface is a carpet having a relatively deep nap, it is desirable to turn the pipe 137 to an angle such that the jets are directed downwardly at a steeper angle, whereby the jets better penetrate the carpet. 0n the other hand, if the surface is a cement or tile floor, it is desirable to discharge the jets of water at a reduced angle. For all angular adjustments of the pipe 137, it has been found that the bulk of the water discharged is picked up by the air stream, and there is no splashing or running of water from the head. The only liquid remaining upon the surface being cleaned is that which may have been temporarily absorbed or which has bee-n used in surface wetting. This is the important feature of our invention because excess wetting of surfaces being cleaned may result in mildewing during subsequent drying. Furthermore it may leave excess amounts of detergent or other chemical upon the surfaces, thus causing deterioration of fabrics.

In the foregoing explanation we have described use of the machine for floor or fabric cleaning. It should be understood, however, that the machine can be used for a wide variety of surface cleaning operations. For example, it can be used on walls or ceilings as well as floors, and upon hanging draperies, upholstery and the like.

In addition to utilizing water together with a dissolved detergent or soap, we can use chemicals such as bleaching agents, disinfectants and the like. Also it is possible to use dyes where it is desired to color a carpet or other fabric, subsequent to cleaning. In addition to the use of water with or without additives it is possible to use other types of liquids, such as carbon tetrachloride or like solvents.

We claim:

1. In an apparatus of the character described, an air blower, a centrifugal separator including a rotatable bowl and a housing for enclosing the bowl, said bowl including means to separate solids from fluids in response to rotation of the bowl, a nozzle adapted to deliver air and liquid into the bowl, together with foreign material to be removed, with impingement upon an inner surface of the bowl to effect rotation thereof, means including the nozzle and the interior of the housing for forming an airflow path to the intake side of the blower, and means for introducing a liquid into the airflow prior to discharge of air through the nozzle.

2. Apparatus as in claim 1 in which the bowl is provided with an annular surface pervious to fluids for collection of solid separated foreign material.

3. Apparatus as in claim 1 in which said housing is formed to provide a liquid collecting reservoir in a space below the bowl together with a pump having its intake side connected to said reservoir, and having its discharge side connected to discharge liquid into said airflow.

4. In apparatus of the character described, means forming an airflow passage, an air blower, a centrifugal separator including a rotatable bowl and a housing for enclosing the bowl, said bowl including means to separate solids from fluids in response to rotation of the bowl, a. nozzle disposed in proximity with the bowl and directed to deliver air and liquid together with foreign material to be removed into the bowl with impingement upon an inner surface of the bowl to effect rotation thereof, said housing being formed to provide a liquid reservoir below the bowl, means including the nozzle and the interior of the housing for forming an airflow path connecting said passage to the intake side of the blower, a liquid pump, the intake side of the pump being connected to said reservoir, connections from the discharge side of the pump to one point in said passage adjacent the nozzle and to another point in said passage remote from said nozzle, and valve means for selectively delivering liquid from the pump to either one of said points.

5. Apparatus as in claim 4 in which the valve means includes a pressure operated valve which when opened delivers liquid to said one point and a manually operated valve which when open permits discharge of liquid to the other point.

6. In apparatus of the character described, means forming an airflow passage, a centrifugal separator including a rotatable bowl and a housing for enclosing the bowl, the bowl being supported for rotation about a vertical axis and including a circular bottom wall and an upright rim, a nozzle within the housing and disposed to discharge into the bowl to effect impingement upon the upper surface of said bottom wall whereby the bowl is rotated, means including the nozzle and the interior of the housing for forming an airflow path from the passage to the intake side of the blower, and means for introducing a liquid into the air flow before discharge of air from said nozzle.

7. In apparatus of the character described, means forming an airflow passage, a housing including a lower part and a removable top part, the lower part forming a liquid collecting reservoir, a centrifugal separating bowl removably supported within the lower part of the housing and rotatable about a vertical axis, a blower carried by the removable top part, the intake side of the blower being in communication with the interior of the housing, a discharge nozzle carried by the top part within the housing and in communication with said passage, the discharge end of said nozzle being directed to effect impingement of air discharged therefrom against a surface of the centrifugal separating bowl, thereby effecting rotation of the bowl, said blower serving to induce flow of air through said passage and through said nozzle, and liquid pumping means carried by the top part and serving to withdraw liquid from the reservoir and to deliver the same into the air stream before discharge thereof from the nozzle.

8. Apparatus as in claim 7 in which the bowl is removably supported within the lower housing part and above the liquid reservoir.

9. Apparatus as in claim 7 together with resilient means for removably supporting the centrifugal separating bowl within the lower part of the housing.

10. In cleaning apparatus of the character described having an applicator head adapted to be traversed over a surface to be treated, the head having an air inlet opening and a passage connected to the opening; a blower, a centrifugal separator including a rotatable bowl and a housing for enclosing the bowl, a nozzle within the housing and serving to deliver air and liquid into the bowl with impingement upon an inner surface of the bowl to effect rotation of the same, a conduit adapted to form an airflow connection between the applicator head and said nozzle, the intake side of the blower being in communication with said housing whereby flow of air is adapted to be induced into the applicator head for discharge into the housing through said nozzle, and means for selectively introducing liquid directly to the nozzle or to the applicator head.

11. In cleaning apparatus of the character described, an applicator head adapted to be traversed over a surface to be treated, the head having an air inlet opening and a passage connected to the opening, a blower, a centrifugal separator including a rotatable bowl and housing for enclosing the bowl, a nozzle within the housing and serving to deliver air and liquid into the bowl with impingement upon an inner surface of the bowl to effect rotation of the same, a conduit forming an air flow connection between the applicator head and said nozzle, the intake side of the blower being in communication with said housing whereby a flow of air is induced into the applicator for discharge into the housing through said nozzle, means for introducing of liquid into the stream of air before discharge from the nozzle, means for introducing liquid into the air flow at a point adjacent to said nozzle, and valve means for selectively supplying liquid to either the applicator head or said last named means.

12. In cleaning apparatus of the character described having an applicator head adapted to be traversed over a surface to be treated, the head having an air inlet opening adapted to be placed in close proximity with said surface and a passage connected to the opening, said head also including means for discharging liquid against the surface to be treated in the region of said opening whereby such liquid is drawn into the air stream after contacting said surface; a housing including a removable top part and a lower part forming a liquid reservoir, a blower carried by said top part of the housing and having its inlet side in communication with the interior of the housing, a centrifugal separator bowl supported within the lower part of the housing for rotation about a vertical axis, a nozzle disposed within the housing and arranged to discharge material into the bowlwith impingement upon an inner surface of the bowl to eflect rotation thereof, an extended conduit adapted to connect the nozzle exteriorly of the housing with said applicator head, a liquid pump carried by the top part of the housing, means establishingcommunication between the inlet side of the pump and the lower portion of the housing, means adapted to form a connection between the discharge side of the pump and the means on the applicator head for discharging liquid and control means for selectively applying the liquid from said pump directly to said nozzle or to said applicator head.

13. In cleaning apparatus of the character described, an applicator head adapted to be traversed over a surface to be treated, the head having an air inlet opening adapted to be placed in close proximity with said surface and a passage connected to the opening, said head also including means for discharging liquid against the surface to be treated in the region of said opening whereby such liquid is drawn into the airstream after contacting said surface, a housing including a removable top part and a lower part forming a liquid reservoir, a blower carried by said top part of the housing and having its inlet side in communication with the interior of the housing, a centrifugal separator bowl supported within the lower part of the housing for rotation about a vertical axis, a nozzle disposed within the housing and arranged to discharge the material into the bowl with impingement upon the inner surface of the bowl to elfect rotation thereof, an extended conduit serving to connect the nozzle exteriorally of the housing with said applicator head, a liquid pump carried by the top part of the housing, means establishing communication between the inlet side of the pump and the lower portion of the housing, means forming a connection between the discharge side of the pump and the means on the applicator head for discharging liquid, means for introducing liquid into said nozzle, and valve means for selectively connecting either the liquid discharge means of the applicator head or said last named means to the discharge side of said pump.

14. An apparatus of the character described, a centrifugal separating bowl, said bowl including a bottom wall and an upstanding annular rim, means serving to support the bowl for rotation about a vertical axis, an entrainment device removably seated upon said bowl, the entrainment device including a downwardly extending annular rim embracing the rim of the centrifugal separating bowl, material discharging over the upper lip of the first named rim being caused to progress downwardly along the inner surface of said second named rim to be discharged from the lower edge of the same, and a porous mat forming a lining for the second named rim.

15. In apparatus of the character described, a centrifugal separating bowl, said bowl including a bottom wall and an upstanding annular rim, means serving to support the bowl for rotation about a vertical axis, and an entrainment device removably seated upon said bowl for rotation with the bowl, the entrainment device including a downwardly extending annular rim embracing the rim of the centrifugal separating bowl, and means forming a screen overlying the upper edge of the rim of the centrifugal separating bowl, material discharging over the upper lip of the first named rim passing throughsaid screen and being caused to progress downwardly along the inner surface of said second named rim to be discharged from the lower edge of the same.

16. In a vacuum cleaning machine of the type having an applicator head adapted to be traversed over a surface to be treated, the head having an air inlet opening adapted to be placed in close proximity with said surface, the machine also having means forming a suction air passage connected to the head and means for discharging liquid into the air stream flowing through the passage; a housing including a removable top part and a lower part forming a liquid reservoir, a blower carried by said top part of the housing and having its inlet side in communication with the interior of the housing, a centrifugal separator bowl supported within the lower part of the housing for rotation about a vertical axis, a nozzle disposed within the housing forming one end of said passage and arranged to discharge material into the bowl with impingement upon a surface of the bowl to effect rotation thereof, a liquid pump carried by the top part of the housing, means establishing communication between the inlet side of the pump and the lower portion of the housing, and means including a distributing valve for forming a connection between the discharge side of the pump and the applicator head and said nozzle, said valve means serving to selectively discharge liquid to either applicator head or said nozzle.

17. In apparatus of the character described, means forming an air flow passage, a housing including a lower part and a removable top part, the lower part forming a liquid collecting reservoir, a centrifugal separating bowl removably supported within the lower part of the housing and rotatable about a vertical axis, a blower carried by the removable top part, the intake side of the blower being in communication with the interior of the housing, a discharge nozzle carried within the housing and in communication with said passage, the discharge end of said nozzle being directed to effect impingement of air discharged therefrom against an inner surface of the centrifugal separating bowl thereby effecting rotation of the bowl, said blower serving to induce flow of air through said passage and through said nozzle, and liquid pumping means carried within the housing and serving to withdraw liquid from the reservoir and to deliver the same into the airstream before discharge thereof from the nozzle.

18. Apparatus as in claim 17 together with an entrainment device removably seated on said bowl, the entrainment device including a downwardly extending annular rim embracing the rim of the centrifugal separating bowl whereby material discharged over the rim of the bowl is caused to progress downwardly along the inner surface of said second named rim to be discharged from the lower edge of the same.

19. Apparatus as in claim 18 in which the entrainment device is provided with a porous mat forming a lining for the second named rim.

20. Apparatus as in claim 18 together with means forming a screen overlying the upper edge of the rim of said bowl and through which the material discharged over the rim from the bowl must flow to pass on to the inner surface of the downwardly extending annular rim.

21. Apparatus as in claim 17 together with sole motive means for driving said blower and said pumping means.

22. In apparatus of the character described, means forming an air flow passage, a housing including a lower part and a top part, the lower part forming a liquid collecting reservoir, a centrifugal separating bowl removably supported within the lower part of the housing and rotatable about a vertical axis, a blower carried by the top part, an open ended shell in communication with the intake side of said blower and extending into said centrifugal separating bowl, a discharge nozzle carried within the housing and in communication with said passage, the discharge end of said nozzle being directed to effect impingement of air discharged therefrom against the surface of the centrifugal separating bowl underlying said shell thereby effecting rotation of the bowl, said blower serving to induce the flow of air through said passage 111 and through said nozzle, and liquid pumping means carried by the housing and serving to withdraw liquid from the reservoir and to deliver the same into the airstream before discharge thereof from the nozzle.

23. Apparatus as in claim 22 together with sole motive means for operating said blower and said liquid pumping means.

24. Apparatus as in claim 23 wherein said pumping means is mounted within said shell.

References Cited in the file of this patent UNITED STATES PATENTS 742,880 Lotz Nov. 3, 1903 813,282 Dutcher Feb. 20, 1906 1,363,860 Fetters et a1 Dec. 28, 1920 1,633,796 Sinclair June 28, 1927 Keefer Mar. 6, Monk Nov. 13, Dunham Feb. 21, Kirby Mar. 13, Kenny Nov. 17, Crites Aug. 11, Child Aug. 18, Hennessy May 18, Gilliam Sept. 7, Emmert et a1. Jan. 25, Tinker July 26,

FOREIGN PATENTS Germany Jan. 4, Great Britain Apr. 18, France Dec. 26, 

